20978700 has 36 divisors (see below), whose sum is σ = 60699240. Its totient is φ = 5594240.

The previous prime is 20978681. The next prime is 20978701. The reversal of 20978700 is 787902.

It is not an unprimeable number, because it can be changed into a prime (20978701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 34665 + ... + 35264.

It is an arithmetic number, because the mean of its divisors is an integer number (1686090).

Almost surely, 2^20978700 is an apocalyptic number.

20978700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20978700 is an abundant number, since it is smaller than the sum of its proper divisors (39720540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20978700 is a wasteful number, since it uses less digits than its factorization.

20978700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 69946 (or 69939 counting only the distinct ones).

The product of its (nonzero) digits is 7056, while the sum is 33.

The square root of 20978700 is about 4580.2510848206. The cubic root of 20978700 is about 275.7991081709.

The spelling of 20978700 in words is "twenty million, nine hundred seventy-eight thousand, seven hundred".